伊索贝尔·惠特科姆　雷婷

One thousand years before the first Fourth of July1， the first fireworks exploded2. It didnt rain twinkling stars or light up the night sky—but to the complete surprise and misfortune of one Chinese chemist3， it did go “bang.”

This “bang” was the product of an ancient quest for immortality， according to Gunpowder， Explosives and the State： A History （Routledge4， 2016）. In early-ninth-century China， alchemy5 was all the rage6. The goal of alchemy was to produce a substance that would prolong life， or even cheat death. Alchemy never did uncover a death-defying7 concoction8. But it did produce an explosion that would change the way we celebrate holidays worldwide.

An explosion requires just three components. First， there must be a fuel—a chemical consisting of long， chain like molecules9 with very strong bonds. Then， there must be a chemical called an oxidizer10. The oxidizer breaks those bonds， releasing tremendous11 energy in the process. Finally， you need heat to get the explosive reaction going.

In hopes of producing a new life-prolonging powder， the unsuspecting12 creator of fireworks mixed charcoal—the perfect fuel—with potassium nitrate13， a common food preservative at the time and a strong oxidizer. The addition of sulfur14 would have lowered the ignition15 temperature of charcoal. With a little heat to prod the reaction forward， the powder exploded. As one Chinese text dating from the mid-ninth century remarked： “Smoke and flames result， so that [the scientists] hands and faces have been burnt， and even the whole house where they were working burned down.”16

Stuffed17 in bamboo， or in a paper tube， the new concoction exploded in religious ceremonies and at the commencement of the new year， Smithsonian Magazine18 reported. The loud noise it made when tossed into19 a fire was thought to scare off evil spirits. （Awe-inspiring20 pyrotechnic21 displays wouldnt come until much later—these early fireworks were all about the bang.）

But the chemistry experiment didnt just produce the earliest fireworks. The concoction， later called gunpowder， was also used in warfare. By the 13th century， gunpowder was used to propel rockets painted like dragons toward invading Mongols， and it was in that same century that Marco Polo brought the stuff back to Europe.

Today， with modern， colorful chemicals at our disposal， pyrotechnicians22 can put on dazzling23 displays unheard of in ninth-century China. But for the bang and the explosion， we can thank the quest for immortality.

早于美国独立日一千年，第一颗烟花爆炸了。它并没有璨若流星或者点亮夜空，而是“砰”的一声炸了，对一名中国炼金术士来说，这是始料未及的飞来横祸。

按《火药、炸药与国家：一部史书》（劳特利奇出版社，2016年）所说，这声“砰”是古代长生不老梦的产物。在9世纪初的中国，炼金术风靡一时。其目的是炼出一种让人延年益寿甚至长生不老的物质。炼金术从来没有造出过长生不老药，反倒产生了爆炸，改变了全球庆祝节日的方式。

爆炸只需要三个因素。首先，必须有一种燃料——一种由长链状分子和非常牢固的键组成的化学制品。然后，必须有一种叫作氧化剂的化学制品。氧化剂会破坏这些键，并在此过程中释放出巨大的能量。最后，需要加热使爆炸反应持续进行。

为了创制一种新的长生不老药粉，烟花的发明者将木炭（完美的燃料）和硝石（当时常见的食品防腐剂和强氧化剂）混合在一起，并添加硫黄以降低木炭的燃点。没想到刚一加热促进反应，粉末就爆炸了。如中国9世纪中叶的一部文献所记载：“焰起，烧手面及火尽屋舍。”

据《史密森尼杂志》报道，人们会在宗教仪式上和新年伊始点燃塞满这种新型混合物的竹子或纸管。将其扔进火中迸发出的巨大声响被认为可以吓退邪灵。 （令人啧啧称奇的烟花表演要等到很久以后才会出现，这些早期的烟花主要就是听个响。）

化学实验不仅产生了最早的烟花。这种被后世称之为火药的混合物也用于战争。到了13世纪，火药已被用来推动画成龙形的火箭射向入侵的蒙古人;在同一世纪，马可·波罗将其运回欧洲。

如今，烟火技师可以凭借多彩的现代化学制品展现9世纪的中国闻所未闻的绚烂景象。但为了这砰砰声和爆炸，我们得感谢对长生不老的追求。

（译者为“《英语世界》杯”翻译大赛获奖者）

1美国于1776年7月4日在费城正式通过独立宣言，因此，7月4日被定为美国独立日。  2 explode爆炸;推翻。  3 chemist炼金术士。  4劳特利奇出版社本部位于英国伦敦，是一家主要在伦敦和纽约两地发行的国际性出版公司。  5 alchemy炼金术。  6 rage肆虐;流行。  7 defy挑衅，对抗。  8 concoction混合物。

9 molecule分子;微粒。  10 oxidizer氧化剂。  11 tremendous巨大的。  12 unsuspecting无怀疑的。文中为了通顺将其调整到下句译出。  13 potassium nitrate硝酸鉀;火硝。  14 sulfur硫，硫黄。  15 ignition点火，着火。  16见唐末五代郑思远所著《真元妙道要略》。  17 stuff填充。  18隶属于美国史密森尼学会的一本杂志。史密森尼学会是唯一由美国政府资助的半官方性质的博物馆机构。  19 toss into扔进。

20 awe-inspiring令人惊叹的，令人敬畏的。  21 pyrotechnic烟火的。  22 pyrotech-nician烟火技师。  23 dazzling辉煌的，炫目的。